Major Engine Problem 7.3

[rodymartin]

was pulling out of the store in my 1990 f250 and the engine started knocking. I pushed the clutch in to coast it to the side of the road and the engine locked. I then went to restart and it is locked up. Checked the engine oil and it is 2x what it should be. it is not water this I can tell as is not milky. So what can it be????

I just back rotated it a bit to see if it would turn. it turn about 1/2 to 3/4 a turn then locked again. When I rotated it sounded like something fell in the pan.

I just dumped the oil in a 5 gallon bucket and was going to filter it to see if there was metal in it. what came out was about 2 gallons of coolant and 2.5 gallons of oil. I checked the oil yesterday or the day before and it was good. I think I have broke the block to water jacket?

Does anyone have any ideas what this could be?

I have a 6.9 that I can install. Will this fit with out to much trouble?

 

[69oiler]

the 6.9 is a direct drop in. welcome to the site and sorry about your luck.

 

[6 Nebraska IDIs]

Wow, sounds about like my families luck. Sorry to hear about that.
You'll like the 6.9 better. Wont have to worry about cavitation of the block.

 

[oldmisterbill]

I swallowed a valve in a 6.9 once it droke the piston and the wristpin went thru the cyinderwall filling the crankase with coolent.Your sounds like a good senerio for this.

 

[rodymartin]

the 6.9 is a direct drop in. welcome to the site and sorry about your luck.

The 7.3 has a ZF 5 sp The 6.9 had a 4 sp behind it. How much problem am I going to have with that??

 

[Cat_Rebel]

The 7.3 has a ZF 5 sp The 6.9 had a 4 sp behind it. How much problem am I going to have with that??

Should be able to just bolt the ZF5 right up to the 6.9L

 

[icanfixall]

Use the flywheel and clutch off what you have in the truck now. Things will bolt up directly but.... If the spare motor came out of a van you will need to change the oil cooler rear header and the drivers side exhaust manifold. You probably should change the oil cooler bundle o-rings now while its out of the of the truck. Its much easier than laying on your back under the truck with oil and coolant dripping down on you....

 

[rodymartin]

Use the flywheel and clutch off what you have in the truck now. Things will bolt up directly but.... If the spare motor came out of a van you will need to change the oil cooler rear header and the drivers side exhaust manifold. You probably should change the oil cooler bundle o-rings now while its out of the of the truck. Its much easier than laying on your back under the truck with oil and coolant dripping down on you....

I have been doing a little research. What I have found is that the clutch in the 7.3 is a Dual mass the 6.9 has a Single mass. What is said is they are interchangeable. Is this true.

 

[flatlander]

the clutch should be specific to the trans, not the motor. So if you want to reuse the zf5, then you'll need the dual mass flywheel.

I don't think that the flywheel's are interchangeable between the zf and the t19.

 

[rodymartin]

Are they interchangeable between the 7.3 and the 6.9 with out balance problems?

 

[Diesel JD]

There's been a lot of debate about that issue. Ford always said never to swap flywheel's or harmonic balancers around but then they used a ZF5 with a Dual Mass flywheel themselves behind some 87s with the 6.9 no balance problems there and there have been many people to do transmission swaps and be good to go. I'd throw that 6.9 in there with no hesitation assuming its a good engine and use your ZF5 from behind your dead motor. You might also replace the head gaskets on the 6.9 while its out and do those oil cooler orings as mentioned. About $150 worth of cheap insurance.

 

[rodymartin]

Here is the the pieces that have to be swaped from the 7.3 to the 6.9 if they can.

tower and gear for the fuel pump
plate for the rear main seal
pan has to have a new gasket
left side exhaust manifold

can this be done??

 

[typ4]

YES< GET IT DONE> It is a direct bolt in ,the block and all accessory bolts are identical. You wont have a flywheel problem, use everything off the truck. .Pull the valve covers and see if the 7.3 dropped a valve, this is just a little research project of mine.
BTW whhere are you located?

 

[hesutton]

I swapped a 7.3 into my '86 (see sig). I'm using the 6.9 flywheel and T19 tranny. There is no vibration/balance issues. The '87 6.9 with the ZF5 uses the same dual-mass flywheel as the 7.3 IDI. The LuK SMF kit is the same for the both 6.9 and 7.3 IDI. The cranks are the same as well.

Heath

 

[G. Mann]

If you use the ZF 5 speed trans you will need the motor plate that bolts to back of the engine off the 7.3 and goes with the ZF.... if you don't, the 5 speed will not bolt up.... bolt spacing is different between the 4 speed and ZF 5 speed at the bell housing. Use the 7.3 flywheel and clutch.. it will bolt up fine...

Otherwise the 6.9 should drop right in on everything else.

Good luck